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Synthetic Transmission and Differential Fluids

Synthetic Transmission and Differential Fluids

Synthetic Transmission and Differential Fluids

(OP)
Manufacturers of synthetic fluids all claim that friction is reduced to the degree that drivetrain losses are reduced, and a power increase can be realized at the wheels.

Is this simply marketing BS?  Have any of the auto manufacturers done testing to validate this?

PY

RE: Synthetic Transmission and Differential Fluids

Sure.  The SAE has done extensive testing as has the oil
industry(API) and private manufacturers.  There is no
question that certain synthetic oils reduce internal
friction and extend service life.  The real question is,
how much, for how long, under what conditions, and, are
synthetic oils cost effective? (marketing hype tends to
leave that data out)

Every dyno test I've seen shows the improvements to be
somewhere between non existant to about 2% improvement
depending on the product tested, it's application, the
vehicle, testing conditions, etc., etc., etc.  The same
oil in a different vehicle under different conditions
could test out showing no benefit whatsoever.  Go figure!
You gotta do your own homework and generalazitions are
worth about what you pay for them!!!!

Hope this helps!

Chumley

RE: Synthetic Transmission and Differential Fluids

The even greater gain in the Diff happen when 90W140 is replaced with 75W90. I have seen gains in chassis dyno's every time with this one. I also changed over to the 75W90 on my wifes suburban. It calls for 80W90 and no doubt it was 90W140 that came out. It had been changed before as evidenced by the silicone around the cover, and it was not dirty, just thick. Once the light stuff was in, I gained 150 miles on a tank, about 37 Gallons is all it will take if it is still running when I fill it up, so you can do the math: 575 miles VS 725.

Good luck,

Shaun Tiede

RE: Synthetic Transmission and Differential Fluids

There must be some substance to this.  Ford is putting synthetic in all the light truck differentials.  They also recommend never changing it unless you make a repair or completely submerge the axle(s) while off-roading, which is consistent with pre-synthetic recommendations, so they're not going to make back the cost in selling replacement Ford branded fluid.  So if its not for generating spare parts profits, they must be seeing an incremental improvement in MPG.

Blacksmith

RE: Synthetic Transmission and Differential Fluids

Perhaps. If I was an OEM, reather than trying to create parts business, I would be building them as reliable as possible.  By doing this, I feel that I will be investing in my future profits because of repeat business from customers that say they'd buy another one in a heart beat. How many people have said that was the first one and the last one I'll ever buy? The company may have made a ton of money on him, but only once. He'll never have a profut from that customer again. And besides, consider the draw backs to the negative advertising these pissed off clients cause.

If the OEM would have flown right in the first place, and stood behind his product, all of this would have been avoided

Shaun TiedeULTRADYNE Arl,TX(stiede@ev1.net)

RE: Synthetic Transmission and Differential Fluids

Shaun, I think you missed the point of TheBlacksmiths post. His point (as I read it) is that there must be something to it, because the manufacturer (in this case Ford) felt the need to spend the money on synthetic diff fluids over conventional. They also reccomend not replacing the fluid as general maintenance, therefore removing the suspicion that they only want you to change the lube to make more money by selling you diff lube. So they are spending more money on the fluid, reccomending that you don't change the fluid unless you absolutely need to (thereby losing money in parts sales), so there must be another reason for them to do this. Thats how I read his post anyway...


-=Whittey=-

RE: Synthetic Transmission and Differential Fluids

I feel you are likely right. I thought a bit more about it also. Perhaps it saves them from eating parts long enough to run past the warranty. Maybe it also helps them extend the warranty. I don't know. I do know that with these deep pocket folk's it is more about the BOTTOM LINE than anything elso. One will definately get additional education about THAT point if ever they are forced as I have been, to pursue legal action against them. (I sued a big deep pocket in another industry.)    

Shaun TiedeULTRADYNE Arl,TX(stiede@ev1.net)

RE: Synthetic Transmission and Differential Fluids

Blacksmith, Whitty---And you guys think I am the cynic!


Rod

RE: Synthetic Transmission and Differential Fluids

That was my point - they're not decreasing maintenance or benefiting from higher priced replacements, so at least their testing, on their synthetic formulation showed an increase in MPG or they wouldn't use it.  I'm not being cynical, believe it or not, they try to put out a good product while pinching pennies on per unit costs, so when I see them use synthetics, platinum spark plugs, etc, I figure there must be some merit to it.  Notice no major OEM is using 3 and 4 electrode spark plugs, tornado fuel savers, the now infamous fuel line magnet, etc.

Blacksmith

RE: Synthetic Transmission and Differential Fluids

As Chumley says, there have been some papers reporting measureable reduced frictional losses for synthetic gear oil basestocks in the order of PAO>ester>mineral oils FOR THE SAME VISCOSITIES, i.e. chemistry has an effect independent of viscosity.  Presumably the OEMs have evaluated the higher lubricant cost versus the small mileage advantage (reportedly worth over $1B/%mpg increase) and determined they make more money indirectly by equipping synthetic.  Fill-for-life is a bonus for the customer.

RE: Synthetic Transmission and Differential Fluids

As all of us know, the EPA play's with them about anything. The mileage gains could likely be another step in helping them avoid or at least minimize the "fleet tax/penalty."

Shaun TiedeULTRADYNE Arl,TX(stiede@ev1.net)

RE: Synthetic Transmission and Differential Fluids

I'm baffled by the argument here.

We have to test the emissions and the fuel consumption of the car to sell it. One way of reducing those numbers is to fit synthetic oil. Another way might be to do something else, say aluminium suspension arms. Somebody makes a $/ mpg reduction decision, and you get synthetics or the suspension arms, or neither, or both. We do whichever is most profitable (we hope).

There's also the warranty thing. If we fit oil that is not deemed acceptable by the diff manufacturer then he won't pay his warranty. Synthetics have a higher temperature rating than  conventional diff oil, so in some applications they are necessary.

Cheers

Greg Locock

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